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Planning on putting my HDD in the Optibay and my SSD in the main drive slot.

Is SMS only useful in case I drop the machine?

like your hinting at, the shock protection for knocks or drops makes it wiser to have the HDD in the main bay and SSD in the optibay, but i think its safe to say others have done it the other way too
 
SSD at optibay may have hibernate issues.

SMS to function best to have rotating HDD in original bay.

which goes where i a personal thing. each have their pros and cons
 
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